Tray for containing foodstuffs and luxury foods which give off liquids

ABSTRACT

Trays are known with two waterproof plastic plies, between which an absorbent paper insert is located, the upper ply ( 12 ) having openings ( 14 ) for passage of liquid. Re-use of these trays requires separation of the insert from the other plies. According to the invention, the insert ( 13 ) also consists of a plastic, i.e. of an open-cell foam plastic. All three plies ( 11, 12, 13 ) are compressed together in the area of a surrounding rim ( 21 ) so that the insert ( 13 ) is no longer open-celled or absorbent in this area.

The invention relates to a tray for containing foodstuffs and luxuryfoods giving off liquids, particularly meat, fish or poultry, with abasic tray member having a base, side walls and transverse side walls,and which has at least two outer plies of waterproof plastic and anabsorbent layer located between the plies, openings being provided inthe upper ply facing the foodstuffs and luxury foods, for passage of theliquid into the absorbent layer.

Previous trays of the type named have an absorbent layer of paper,cellulose or the like. Re-use of such a tray, consisting for example ofplastics, in the sense of a closed circuit, is difficult, as the layer(not consisting of plastic) must firstly be separated in a complexprocess.

On this basis it is the object of the present invention to provide atray which may be simply re-used and nevertheless has a good capacityfor absorbing liquid.

The purpose is achieved according to the invention in that the absorbentlayer consists of an open-celled plastic preferably of an open-celledfoam plastic. In contrast to other plies, this layer is not waterproofand thus absorbs the separated liquid into its open cells. Separation ofthe individual plies or of the layer in this construction is no longernecessary for re-use of old materials, as the outer plies and theabsorbent layer consist entirely of plastic.

More advantageously, the lower ply consists of a closed-cell foamplastic, whilst the upper ply is produced from a compact, i.e.non-foamed plastic, particularly from a sheet. The closed-cell foamplastic is soft, pleasant to handle, has a high heat insulating effectand is waterproof. The upper compact ply has a relatively smooth surfaceand thus is pleasant in appearance. In the non-visible (lined)construction, the central absorbent layer is hidden from view, as arethe liquids which have penetrated the absorbent layer, for examplereddish meat juice. The upper compact ply can optionally be eithercoloured or uncoloured. Alternatively it may also be envisaged toassociate with the outer side of the lower ply a further lowermost plyof compact plastics, particularly a sheet. The tray is then constructedin four plies or four layers. This additional lowermost ply cancorrespond to the upper ply, i.e. can be either coloured or uncoloured.

It is particularly advantageous if, in addition to the formation of thelower ply from closed-cell foam plastic, the (central) absorbent layerconsists of open-cell foam plastic. The material involved here istotally open-celled, e.g. foam plastic. Correspondingly, the lower plyis formed from entirely closed-celled, e.g. foam plastic. In this waythere is a separation of the tray which complies with requirements. Thisseparation is also advantageous because the layer and the ply may beparticularly easily formed either from entirely open-cell or closed-cellfoam plastic. In this connection, entirely open-cell foam plastic orentirely closed-cell foam plastic means that, during manufacture of thecorresponding layer or ply, an attempt is made to obtain either as manyclosed or as many open-cells as possible. In the ideal case all, i.e.100% of the cells would either be open or closed. This ideal casehowever is not always achieved in practice, so that the absorbent layer,made of open-cell foam plastic, contains open cells to a small degree,and the lower ply made of closed-cell foam plastic, contains open cellsto a small degree. As a rule, in the case of closed-cell foam plastics,at least 90% of the cells are closed, while with open-cell foam plasticsat least 90% of the cells are open. Accordingly, when entirely closedcells are mentioned, this is to be taken to mean a foam plastic in whichas many cells as possible are closed, but also a small proportion of thecells can be open. Conversely, in the case of an open-cell foam plastic,the majority of the cells are open, while a small proportion of thecells can be closed.

The invention further relates to a surrounding edge of the tray. The twoplies are compressed together with the absorbent layer in the area ofthe surrounding edge, in such a way that the layer is no longeropen-celled in this lateral area. For this purpose, the layer in thearea of the surrounding edge of the tray is preferably partly compacted.The lateral area of the layer is rendered non-cellular by means of thecompression procedure. Thus the absorbed liquid cannot pass out over theedge. In addition, the lateral compression is only carried out to such adegree that the lower ply in the lateral area does in fact losestrength, but remains flexible and thus is not compacted.

In this way sharp edges in the area of the surrounding rim are avoided.According to an advantageous further development of the invention, thebase wall of the tray is at least partly curved in configuration. Thiscurvature is of such type that at least the inner wall of the tray, uponwhich the articles to be contained by the tray rest, has a curvature.The curvature is such that the highest point is located roughly in thecentre of the base wall. From this point the base wall drops away to theside walls or the transverse side walls. Thus the liquid accumulating inthe interior of the tray can run off to the edges of the base wall oraccumulate there. In this case the lateral areas of the base walladjacent to the side walls and the lateral side walls must not becurved. Preferably, openings for removing the liquid to the absorbentlayer are provided in the lateral areas of the base wall adjacent to theside walls and transverse walls, so that the liquids can also be removedat that point to which they have been passed due to the raised centre ofthe base wall. Further features of the invention will become apparentfrom the sub-claims.

Preferred embodiments of the invention, given by way of example will beexplained in more detail in the following with reference to drawings,which show:

FIG. 1: a plan view of a tray according to the invention,

FIG. 2: a cross-section of the tray along line II—II in FIG. 1,

FIG. 3: an enlarged cross-section similar to the cross-sectional view inFIG. 2, yet in the area of an opening for the passage of liquids,

FIG. 4: an enlarged detail IV—IV from FIG. 2 in the area of a rim of thetray,

FIG. 5: a plan view of a second embodiment of a tray according to theinvention,

FIG. 6: a cross-section of the tray along line V—V in FIG. 5,

FIG. 7: an enlarged detail VI from FIG. 5 in the area of an opening in abase wall,

FIG. 8: a cross-section through the opening in FIG. 7 along the lineVII—VII.

The trays shown here are in three-layer form and are entirely made ofplastic.

The tray 10 shown in FIGS. 1 to 4 has a lower ply 11 of liquid-typeplastic, particularly of entirely closed-cell foam plastic, an upper ply12 of liquid-type plastic particularly a compact, non-foamed plastic ormade from a sheet, and an absorbent layer 13 located between the plies11, 12. The outer walls of the two outer plies 11, 12 form a so-calledbasic tray member. The plies 11, 12, of equal size, and the layer 13, ofcorresponding size, are connected together substantially over theirentire surface.

The absorbent layer 13 in the present case likewise consists of plastic,i.e. of an open-cell plastic, preferably an entirely open-cell foamplastic. The layer 13 is thus suitable for absorbing or taking upliquids.

The upper ply 12 has a plurality of openings 14 at regular or irregularintervals. The openings 14 can extend entirely or partly through thelayer 13. FIG. 3 shows an alternative, i.e. openings 14 produced bystamping, forming an aperture tab 15, which is pressed into the layer 13and thus forms at that point a recess 16 as a continuation of opening14. The liquids given off by a piece of meat, fish or poultry in thetray can flow out through the openings 14 into the layer 13 and areabsorbed or retained by the open cells of the layer 13.

The basic tray body of the tray 10 has in a previously known way a flatbase wall 22 and obliquely upwardly aligned side walls 17, 18 andcorresponding transverse side walls 19, 20. The side walls 17, 18 andtransverse walls 19, 20 surround the base wall 22. Connecting with thesaid side walls 17, 18 and transverse walls 19, 20 in an outwarddirection is a surrounding rim 21. This is formed by compression of thetwo plies 11, 12 and of layer 13. Thus the two plies 11, 12 and thelayer 13, of equal size, extend over the entire width and length of thetray 10.

The individual plies 11, 12 and the layer 13 are compressed together inthe surrounding rim 21 to such an extent that the absorbent layer 13 inthis area has lost its absorbent, open-celled property (FIG. 4). In thisarea the layer 13 is waterproof, i.e. by means of entire or partialcompacting. Accordingly, no liquid can emerge out of the surrounding rim21. In FIG. 4, the compacted region of the ply 12 and of the layer 13has the width R. In this area R the layer 13 is compacted down to thethickness of the ply 12. Both are thus of roughly the same thickness;i.e. they have a respective thickness of about 0.4 mm. Due to thecompacting of the layer 13 in the region R of the surrounding rim 21,this latter forms with the adjacent ply 12 a unified compacted plasticrim.

Finally, the surrounding rim 21 is so compressed that the lower play 11is in fact reduced in thickness in this area, but remains flexible,being only partly compacted. In this area of reduced thickness (“R” inFIG. 4, the ply has a thickness of preferably only 1 to 2 mm. Thesurrounding rim 21 thus feels relatively soft, at least from below.There are no sharp edges. The described flexibility of the lower ply 11and the compacting of layer 13 in the surrounding rim 21 may be achievedsimultaneously, and do not exclude one another (FIG. 4).

In the region of the base wall 22 and in the region of the walls 17 to20, the ply 11 has the greatest thickness. The absorbent layer 13 isslightly thinner, while the upper ply 12, due to its compact structure,is extremely thin both relative to the lower ply 11 and also to thelayer 13. The lower ply 11 and the layer 13 are produced from layers ofidentical density and/or thickness. During manufacture of the tray 10 ina deep-drawing process with preceding heating, the lower ply 11 expands,due to the closed cells, to a greater degree than the absorbent layer 13with open cells.

Thus the thicker lower ply 11 results relative to the layer 13.

As FIG. 1 shows, the openings 14 are provided only in the opening of thebase wall 22. Corresponding openings 14 may however also be provided inthe region of the side wall 17, 18 and/or of the transverse side walls19, 20.

FIGS. 5 to 8 show a tray 23 according to a second embodiment of theinvention. The tray 23 is also in a three-layer form. The tray 23, liketray 10, has a lower ply 24 of waterproof plastic, particularly ofentirely closed-cell foam plastic, an upper ply 25 of waterproofplastic, particularly of a compact non-foamed plastic, for example asheet, and an absorbent layer 26 located between the plies 24 and 25.The absorbent layer 26 also consists of a plastic, i.e. of an open-cellplastic, preferably an entirely open-celled foam plastic.

The tray 23 has a basic tray body which corresponds in form to the basictray body of the tray 10 of FIGS. 2 to 4. In this respect reference ismade to the description of tray 10, identical reference numbersidentifying identical parts.

In tray 23 also, the plies 24 and 25, and the layer 26, with respect totheir surface areas, are of equal size. The conditions of thickness ofplies 24, 25 and of the layer 26 roughly correspond to those of the tray10 in FIGS. 1 to 4. Also, the surrounding rim 21 of the tray 23 iswaterproof, the liquid-absorbing layer 26 in the area of the surroundingrim 21 being at least compressed in such a way that its cells are closedand thus no liquids can flow outwards over the rim 21. The plies 24 and25 are substantially connected over their entire surface with theintermediate layer 26, as is the case with the tray 10 in FIGS. 1 to 4.

In contrast to tray 10, in the tray 23 the base wall 27 is slightlycurved. This curvature is such that the highest point is located roughlyin the centre of the base wall 27 and from this point extends downwardsboth the side walls 17 and 18 and to the transverse side walls 19, 20.This inclination of the base wall 27 aligned towards the edges of thetray 23 terminates shortly before the side walls 17 and 18 and thetransverse side walls 19 and 20, so that lateral areas of the base wall27 extend roughly horizontally.

The curvature in the base wall 27 is formed by an absorbent layer 26which is slightly curved only on the upper side. The underside of thecurved layer 26 is flat (FIG. 5). The volume of this absorbent layer 26is in this way increased. Despite the curvature of the base wall 27, theplies 24 and 25 have parallel outer walls, so that the underside of thebase wall 27 of tray 23, delimited by the lower wall of the lower ply24, is flat. The thin upper ply 25 is adapted, in the curved area of thebase wall 27, to the curved configuration of the absorbent layer 26 onlyat the upper side of the same, so that the upper ply 25 has a curvedconfiguration at points, and thus the base wall 27 is curved at least inthe central area on the inner side of the tray 23.

It will be seen from FIG. 5 that the base wall 27 has openings 28 onlyon a partial area of its surface. These openings are located in lateralareas of the base wall 27 adjacent to the side walls 17 and 18 and thetransverse side walls 19 and 20, i.e. preferably on such lateral areasof the base wall 27 which are not curved. In this way the openings 28surround the curved area of the base wall 27. Accumulating liquid in theinterior of the tray 23 can flow from the central highest point of thebase wall 27 to the edges of the base wall 27 and the openings 28located at that point.

In the case of the tray 23, the openings 28 are formed in a special way,i.e. by a cruciform incision. This cruciform incision extendssubstantially through the upper, sheet-like ply 25. Thus in the area ofeach opening 28, the play 25 receives four triangular tabs 29, which arepressed into the central absorbent layer 26. In this way there areprovided, between edges 30 of adjacent tabs 29, intermediate spaces 31,at which the waterproof upper ply 25 does not overlap the absorbentcentral layer 26, so that liquids can pass through the intermediatespaces 31 to the absorbent layer 26 (FIGS. 7 and 8). By means ofpressing the tabs 29 into the layer 26, there results in the area ofeach opening 28 a recess aligned towards the centre of the same in thebase wall 27, so that the flow of liquids to each opening 28 issimplified and intensified.

It may also be envisaged to provide the tray 23 with openings 28 formedor manufactured in another way, and also to undertake the distributionof the openings on the base wall 27 and if necessary also the transverseside walls 19, 20 and/or side walls 17, 18 in a way different from thatshown in FIG. 5.

Finally it may be envisaged to form the trays 10 and 23 from more thanthe two plies 11, 12; 24, 25 and the intermediate absorbent layer 13; 26as shown in FIGS. 1 to 8. For example there may be provided beneath theouter side of the lower ply 11; 24 an additional (lowermost) ply, whichcovers the entire outer side of the lower ply 11; 24. This lowermost plypreferably consists of compact ply, for example a thin sheet similar tothe upper ply 12; 25. The lowermost ply may also be coloured or carry acolour pattern or a printed message.

What is claimed is:
 1. Tray for containing foodstuffs and luxury foodsgiving off liquids, particularly meat, fish or poultry, with a basictray body having a base wall (22), side walls (17, 18) and transverseside walls (19, 20), and which has at least two outer plies (11, 12; 24,25) made of waterproof plastic and an absorbent layer (13; 26) locatedbetween the plies (11, 12; 24, 25), openings (14; 28) being provided inthe upper ply (12; 25) facing the foodstuffs or luxury foods, forpassage of the liquids into the absorbent layer (13; 26), characterizedin that the absorbent layer (13; 26) consists of an open-cell plasticand the openings (14; 28) in the upper ply (12; 25) extend into theabsorbent layer (13; 26).
 2. Tray according to claim 1, characterised inthat the lower ply (11; 24) consists of a closed-cell foam plastic. 3.Tray according to claim 1, characterised in that the upper ply (12; 25)consists of a compact non-foamed plastic, particularly of a sheet with athickness of preferably about 0.4 mm.
 4. Tray according to claim 1,characterised in that the upper ply (12; 25) is substantiallynon-transparent, particularly formed from a coloured, especially dyedsheet.
 5. Tray according to claim 1, characterised in that the absorbentlayer (13; 26) extends as far as a surrounding rim (21).
 6. Trayaccording to claim 5, characterised in that the two plies (11; 12, 24;25)) are compressed together with the absorbent layer (13; 26) lyingtherebetween in the region of the surrounding rim (21).
 7. Trayaccording to claim 6, characterised in that the waterproof plies (11,12; 24,25) and the absorbent layer (13; 26) are pressed together sointensely in the area of the surrounding rim (21) in order to achieve aliquid seal, that the compressed lateral areas of the layer (13; 26) arewaterproof around the periphery, and are preferably compacted with athickness of preferably 0.4 mm.
 8. Tray according to claim 6,characterised in that the two waterproof plies (11, 12; 24, 25) arepressed together with the absorbent layer (13; 26) in the area of thesurrounding rim (21) in such a way that the ply (11; 24) still has, inthe area of the rim (21), closed cells with a residual thickness ofpreferably 1 to 2 mm.
 9. Tray according to claim 5, characterised inthat the two plies (11, 12; 24, 25) are substantially connected overtheir entire surface to the absorbent layer (13; 26) lying therebetween.10. Tray according to claim 1, characterised in that at least the basewall (27) is at least partly curved, in such a way that it extends in adownwards alignment to the side walls (17, 18) and/or the transverseside walls (19, 20).
 11. Tray according to claim 10, characterised inthat at least a part of the opening (28) is located in the areas of thecurved base wall (22) that extend in a downward alignment.
 12. Trayaccording to claim 1, characterised in that it has on the outer side ofthe lower ply (11; 24) an additional outer ply of a compact non-foamedplastic, particularly a sheet.
 13. Tray according to claim 12,characterised in that the ply (11; 24) of closed-cell foam plastic andthe absorbent layer (13; 26) of open-cell foam plastic are locatedbetween the two plies forming the two oppositely-situated outer sides.